26
|
Ahmad QR, Allen RC, Andersen TC, Anglin JD, Bühler G, Barton JC, Beier EW, Bercovitch M, Bigu J, Biller S, Black RA, Blevis I, Boardman RJ, Boger J, Bonvin E, Boulay MG, Bowler MG, Bowles TJ, Brice SJ, Browne MC, Bullard TV, Burritt TH, Cameron K, Cameron J, Chan YD, Chen M, Chen HH, Chen X, Chon MC, Cleveland BT, Clifford ET, Cowan JH, Cowen DF, Cox GA, Dai Y, Dai X, Dalnoki-Veress F, Davidson WF, Doe PJ, Doucas G, Dragowsky MR, Duba CA, Duncan FA, Dunmore J, Earle ED, Elliott SR, Evans HC, Ewan GT, Farine J, Fergani H, Ferraris AP, Ford RJ, Fowler MM, Frame K, Frank ED, Frati W, Germani JV, Gil S, Goldschmidt A, Grant DR, Hahn RL, Hallin AL, Hallman ED, Hamer A, Hamian AA, Haq RU, Hargrove CK, Harvey PJ, Hazama R, Heaton R, Heeger KM, Heintzelman WJ, Heise J, Helmer RL, Hepburn JD, Heron H, Hewett J, Hime A, Howe M, Hykawy JG, Isaac MC, Jagam P, Jelley NA, Jillings C, Jonkmans G, Karn J, Keener PT, Kirch K, Klein JR, Knox AB, Komar RJ, Kouzes R, Kutter T, Kyba CC, Law J, Lawson IT, Lay M, Lee HW, Lesko KT, Leslie JR, Levine I, Locke W, Lowry MM, Luoma S, Lyon J, Majerus S, Mak HB, Marino AD, McCauley N, McDonald AB, McDonald DS, McFarlane K, McGregor G, McLatchie W, Meijer Drees R, Mes H, Mifflin C, Miller GG, Milton G, Moffat BA, Moorhead M, Nally CW, Neubauer MS, Newcomer FM, Ng HS, Noble AJ, Norman EB, Novikov VM, O'Neill M, Okada CE, Ollerhead RW, Omori M, Orrell JL, Oser SM, Poon AW, Radcliffe TJ, Roberge A, Robertson BC, Robertson RG, Rowley JK, Rusu VL, Saettler E, Schaffer KK, Schuelke A, Schwendener MH, Seifert H, Shatkay M, Simpson JJ, Sinclair D, Skensved P, Smith AR, Smith MW, Starinsky N, Steiger TD, Stokstad RG, Storey RS, Sur B, Tafirout R, Tagg N, Tanner NW, Taplin RK, Thorman M, Thornewell P, Trent PT, Tserkovnyak YI, Van Berg R, Van de Water RG, Virtue CJ, Waltham CE, Wang JX, Wark DL, West N, Wilhelmy JB, Wilkerson JF, Wilson J, Wittich P, Wouters JM, Yeh M. Measurement of the rate of nu(e) + d --> p + p + e(-) interactions produced by (8)B solar neutrinos at the Sudbury Neutrino Observatory. PHYSICAL REVIEW LETTERS 2001; 87:071301. [PMID: 11497878 DOI: 10.1103/physrevlett.87.071301] [Citation(s) in RCA: 169] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/18/2001] [Indexed: 05/23/2023]
Abstract
Solar neutrinos from (8)B decay have been detected at the Sudbury Neutrino Observatory via the charged current (CC) reaction on deuterium and the elastic scattering (ES) of electrons. The flux of nu(e)'s is measured by the CC reaction rate to be straight phi(CC)(nu(e)) = 1.75 +/- 0.07(stat)(+0.12)(-0.11)(syst) +/- 0.05(theor) x 10(6) cm(-2) s(-1). Comparison of straight phi(CC)(nu(e)) to the Super-Kamiokande Collaboration's precision value of the flux inferred from the ES reaction yields a 3.3 sigma difference, assuming the systematic uncertainties are normally distributed, providing evidence of an active non- nu(e) component in the solar flux. The total flux of active 8B neutrinos is determined to be 5.44+/-0.99 x 10(6) cm(-2) s(-1).
Collapse
|
27
|
Barton JC, Acton RT. Inheritance of two HFE mutations in African Americans: cases with hemochromatosis phenotypes and estimates of hemochromatosis phenotype frequency. Genet Med 2001; 3:294-300. [PMID: 11478530 DOI: 10.1097/00125817-200107000-00005] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
PURPOSE Two unrelated African Americans had hemochromatosis phenotypes and genotypes. We sought to identify origins of their HFE mutations and estimate frequencies of similar cases. METHODS HFE and HLA genotyping were performed in index cases and family members. HFE genotypes of 1,373 African American controls in five regions were tabulated. RESULTS Index cases had C282Y/C282Y and C282Y/H63D, respectively; each corresponding Ch6p was likely of Caucasian origin. In controls, frequencies of hemochromatosis-associated genotypes were as follows: C282Y/C282Y, 0.00011; C282Y/H63D, 0.00067; and H63D/H63D, 0.00101. CONCLUSIONS Penetrance-adjusted estimates indicate that approximately 9 African Americans per 100,000 have a hemochromatosis phenotype and two common HFE mutations. Hemochromatosis-associated genotype frequencies varied 11.7-fold across regions.
Collapse
|
28
|
Barton JC, Bertoli LF, Rothenberg BE. Screening for hemochromatosis in routine medical care: an evaluation of mean corpuscular volume and mean corpuscular hemoglobin. GENETIC TESTING 2001; 4:103-10. [PMID: 10953947 DOI: 10.1089/10906570050114786] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Our aim was to evaluate the potential utility of mean corpuscular volume (MCV) and mean corpuscular hemoglobin (MCH) to detect hemochromatosis. We computed the accuracy of MCV and MCH cut-off points > or = upper reference limits using data from 94 probands and 132 white controls. Our reference ranges are MCV 80.0-97.0 fL and MCH 26.0-32.0 pg. Sensitivity of MCV was 8.6-48.3% for men and 2.8-44.4% for women (cut-off points > or = 105.0 - > or = 97.0 fL, respectively). Sensitivity of MCH was 33.9-70.7% for men and 19.6-50.0% for women (cut-off points > or = 34.0 - > or = 32.0 pg, respectively). Using MCV and a hemochromatosis frequency typical of many western Caucasian populations (0.005), positive predictive values (PV+) were 2.1-100.0% in men and 4.2-100.0% in women. Using MCH, PV+ were 1.7-8.2% in men and 1.8-6.8% in women. We also calculated PV+ using the hemochromatosis frequency 0.015, which could occur in persons receiving medical care. Using MCV cut-off points > or = 101.0 fL, PV+ were 8.9-100.0% in men and 100.0% in women with maximum sensitivities of 24.1% and 25.0%, respectively. Using MCH testing, PV+ was 21.5% in men (cut-off point > or = 34.0 pg) and 18.2% in women (cut-off point > or = 33.0 pg) with sensitivities of 33.9% and 37.0%, respectively. Using MCV or MCH, sensitivity and PV+ for the HFE genotype C282Y/C282Y were generally greater than for "nonclassical" HFE genotypes. All negative predictive values in our study were > or = 98.5%. We conclude that supranormal values of MCV or MCH could be used to detect hemochromatosis in white persons of western European descent who are receiving routine medical care. Comparisons of MCV, MCH, and transferrin saturation testing and other implications of MCV and MCH testing for hemochromatosis in medical care are discussed.
Collapse
|
29
|
Barton JC, Acton RT. Transferrin saturation phenotype and HFE genotype screening for hemochromatosis and primary iron overload: predictions from a model based on national, racial, and ethnic group composition in central Alabama. GENETIC TESTING 2001; 4:199-206. [PMID: 10953960 DOI: 10.1089/10906570050114911] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
There is interest in general population screening for hemochromatosis and other primary iron overload disorders, although not all persons are at equal risk. We developed a model to estimate the numbers of persons in national, racial, or ethnic population subgroups in Jefferson County, Alabama, who would be detected using transferrin saturation (phenotype) or HFE mutation analysis (genotype) screening. Approximately 62% are Caucasians, 37% are African Americans, and the remainder are Hispanics, Asians, or Native Americans. The predicted phenotype frequencies are greatest in a Caucasian subgroup, ethnicity unspecified, which consists predominantly of persons of Scotch and Irish descent (0.0065 men, 0.0046 women), and in African Americans (0.0089 men, 0.0085 women). Frequencies of the HFE genotype C282Y/C282Y > or = 0.0001 are predicted to occur only among Caucasians; the greatest frequency (0.0080) was predicted to occur in the ethnicity-unspecified Caucasian population. C282Y/C282Y frequency estimates were lower in Italian, Greek, and Jewish subgroups. There is excellent agreement in the numbers of the ethnicity-unspecified Caucasians who would be detected using phenotype and genotype criteria. Our model also indicates that phenotyping would identify more persons with primary iron overload than would genotyping in our Italian Caucasian, Hispanic, and African American subgroups. This is consistent with previous observations that indicate that primary iron overload disorders in persons of southern Italian descent and African Americans are largely attributable to non-HFE alleles. Because the proportions of population subgroups and their genetic constitution may differ significantly in other geographic regions, we suggest that models similar to the present one be constructed to predict optimal screening strategies for primary iron overload disorders.
Collapse
|
30
|
Barton JC, Preston BL, McDonnell SM, Rothenberg BE. Severity of iron overload in hemochromatosis: effect of volunteer blood donation before diagnosis. Transfusion 2001; 41:123-9. [PMID: 11161257 DOI: 10.1046/j.1537-2995.2001.41010123.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND An effort was made to determine if volunteer blood donation before diagnosis decreases the severity of iron overload at diagnosis in persons with hemochromatosis. STUDY DESIGN AND METHODS A study was performed in 1089 persons in the United States with hemochromatosis who responded to a convenience sample survey and in 124 C282Y/C282Y hemochromatosis probands diagnosed during routine medical care. RESULTS Less than half of questionnaire respondents (46.2%) and probands (35.5%) reported that they had been volunteer blood donors; 5.4 percent and 4.0 percent, respectively, had donated >20 units of blood. In either subject group, there were no significant differences according to age in the mean numbers of units that needed to be removed by therapeutic phlebotomy to induce iron depletion in subgroups of men and women, respectively. Similarly, there was no significant correlation of units of voluntary blood donation or of therapeutic phlebotomy index (= therapeutic phlebotomy units/age in years) with the number of therapeutic phlebotomy units needed to induce iron depletion. When questionnaire respondents were stratified by sex, there was no significant correlation of units of blood donation with the number of therapeutic phlebotomy units needed to induce iron depletion or with the therapeutic phlebotomy index. CONCLUSION Routine blood donation does not, on average, decrease the severity of iron overload in persons with hemochromatosis. These findings have implications for the understanding of the severity of iron overload and its complications in hemochromatosis, for advising persons with hemochromatosis about treatment, and for considering persons with hemochromatosis as possible blood donors.
Collapse
|
31
|
Abstract
Thirteen adults (eight men, five women) with hemochromatosis had undergone routine iron depletion therapy but while on maintenance phlebotomies developed iron deficiency which persisted for 25 +/- 13 (mean +/- 1 SD) months before diagnosis. All had symptoms and signs of iron deficiency. Levels of transferrin saturation were 10% +/- 5% (1 SD), and serum ferritin concentrations were 8 +/- 3 ng/mL. Eleven had anemia; eight had hypochromia and microcytosis. Bone marrow specimens obtained in five patients revealed no stainable iron. Medical records indicated that parameters of body iron status were infrequently or incorrectly used for adjusting the frequency of phlebotomies. Two patients developed iron deficiency due to additional blood loss from esophageal varices and bilateral hip replacement, respectively. Ten of the patients were treated with ferrous sulfate, 325 mg daily, for 2-6 weeks when anemia was corrected. In patients who were not given iron, anemia and microcytosis recovered in 8-24 months. We conclude that (i) sustained iron deficiency in hemochromatosis patients should be prevented by monitoring hemoglobin levels and serum ferritin; and (ii) hemoglobin concentrations and values of mean corpuscular hemoglobin may be higher in iron-deficient persons with hemochromatosis than in individuals without hemochromatosis. Symptomatic iron deficiency in hemochromatosis patients may be treated safely with a brief course of ferrous sulfate. Recovery is slower when iron is not given. However, iron supplementation is unnecessary and not recommended for the mild, self-limited anemia and decreased serum iron and ferritin concentrations encountered after initial iron depletion therapy for hemochromatosis.
Collapse
|
32
|
Barber M, Conrad ME, Umbreit JN, Barton JC, Moore EG. Abnormalities of flavin monooxygenase as an etiology for sideroblastic anemia. Am J Hematol 2000; 65:149-53. [PMID: 10996833 DOI: 10.1002/1096-8652(200010)65:2<149::aid-ajh10>3.0.co;2-b] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
We postulated that a deficiency of flavin monooxygenase (FMO)-a ferrireductase component of cells-could produce sideroblastic anemia. FMO is an intracellular ferrireductase which may be responsible for the obligatory reduction of ferric to ferrous iron so that reduced iron can be incorporated into heme by ferrochelatase. Abnormalities of this mechanism could result in accumulation of excess ferric iron in mitochondria of erythroid cells to produce ringed sideroblasts and impair hemoglobin synthesis. To investigate this hypothesis we obtained blood from patients with sideroblastic anemia and normal subjects. Extracts of peripheral blood lymphocytes were used to measure ferrireduction by utilization of NADPH. Lymphoid precursors are reported to accumulate iron in mitochondria similarly to erythroid precursors. Utilization of lymphoid precursors avoided the need for bone marrow aspirations. We studied three patients with sideroblastic anemia. One patient and his asymptomatic daughter had a significant decrease in ferrireductase activity. They also had markedly diminished concentrations of FMO in lymphocyte protein extracts on Western blots. This was accompanied by increased concentration of mobilferrin in the extracts. These results suggest that abnormalities of FMO and mobilferrin may cause sideroblastic anemia and erythropoietic hemochromatosis in some patients.
Collapse
|
33
|
Barton JC, Barton EH, Bertoli LF, Gothard CH, Sherrer JS. Intravenous iron dextran therapy in patients with iron deficiency and normal renal function who failed to respond to or did not tolerate oral iron supplementation. Am J Med 2000; 109:27-32. [PMID: 10936475 DOI: 10.1016/s0002-9343(00)00396-x] [Citation(s) in RCA: 66] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
PURPOSE To evaluate the safety and effectiveness of using 500-mg doses of iron as intravenous iron dextran after premedication with diphenhydramine, cimetidine, and dexamethasone. SUBJECTS AND METHODS We treated 135 iron-deficient adults (26 men, 109 women) with normal renal function (serum creatinine level </=1.5 mg/dL or blood urea nitrogen level </=26 mg/dL) who could not be treated adequately with oral iron supplements due to gastrointestinal symptoms (59%), inadequate hematologic response (39%), severe anemia (19%), or noncompliance (4%). Some patients had more than one reason for treatment. Resolution of iron deficiency was defined as the restoration of transferrin saturation, serum ferritin level, anemia, and abnormal erythrocyte indexes to normal or baseline values. RESULTS Before treatment with iron dextran, patients had a mean (+/- SD) transferrin saturation of 8% +/- 5%, a median serum ferritin level of 11 ng/mL, and a mean hemoglobin level of 10 +/- 2 g/dL. Ninety-two percent were anemic; 60% had unrecognized or untreated causes of anemia other than iron deficiency. We administered 285 iron dextran infusions (median 2, mean 2 infusions per patient; range 1 to 7). Eighty-seven percent of patients had no adverse reaction; 13% had mild reactions, especially arthralgias and myalgias. No patient had an anaphylaxis-like reaction. Fifty-four (40%) patients had resolution of iron deficiency, 34 (25%) continue to receive therapy, 36 (27%) returned to the care of their primary physician, and 11 (8%) died before iron repletion could be achieved. CONCLUSIONS Iron-deficient adults with normal renal function who cannot be treated adequately with oral iron supplements can be treated effectively and safely with this intravenous iron dextran regimen.
Collapse
|
34
|
Barton JC, Bertoli LF. Transfusion iron overload in adults with acute leukemia: manifestations and therapy. Am J Med Sci 2000; 319:73-8. [PMID: 10698089 DOI: 10.1097/00000441-200002000-00001] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
BACKGROUND Hepatic dysfunction occurs commonly among persons successfully treated for acute leukemia, and iron overload is a possible cause of hepatic and other abnormalities in these patients. METHODS We identified 5 adults 40+/-13 (mean +/- S.D.) years of age who developed transfusion iron overload in association with successful chemotherapy of de novo acute leukemia. None had evidence of hemochromatosis, viral hepatitis, or other primary hepatic disorders. RESULTS The mean serum ferritin concentration of our patients was 1531+/-572 ng/mL. Other abnormalities associated with transfusion iron overload were increased stainable iron in bone marrow macrophages, elevated serum concentrations of hepatic enzymes, hyperpigmentation, hyperferremia, elevated iron saturation of serum transferrin, and increased stainable iron in Kupffer cells and hepatocytes. Rheumatologic, endocrinologic, or cardiac abnormalities attributable to iron overload were not observed. Therapeutic phlebotomy was initiated after chemotherapy; recovery of hemoglobin concentrations after phlebotomy permitted weekly treatment in each case. This yielded an average of 28+/-9 units per patient (range 15-35 units). Abnormalities associated with transfusion iron overload resolved after iron depletion therapy. The mean leukemia-free survival of our patients is 96+/-36 months (range 40-125 months). CONCLUSIONS Our data and those of others suggest that 15 to 20% of adults who are long-term survivors of acute leukemia develop iron overload, often with hepatic abnormalities. Iron overload is a relatively common sequela to successful management of acute leukemia in adults for which routine evaluation should be performed and for which therapeutic phlebotomy should be used as treatment.
Collapse
|
35
|
Abstract
Hemochromatosis refers to a group of common heritable disorders among Western Caucasians which increase susceptibility for development of iron overload and its complications. These consequences are preventable by early detection and simple, relatively inexpensive treatment. Screening of appropriate populations to detect hemochromatosis before iron overload occurs is both effective and cost-effective. The primary goal of screening should be the ongoing detection of persons with hemochromatosis, especially healthy individuals whose risk to develop iron overload is great, in a context that provides appropriate preventive treatment, education, and counseling. Although related issues warrant further study, implementation of well-designed screening programs for hemochromatosis should not be delayed.
Collapse
|
36
|
Barton JC, Bertoli LF, Rothenberg BE. Peripheral blood erythrocyte parameters in hemochromatosis: evidence for increased erythrocyte hemoglobin content. THE JOURNAL OF LABORATORY AND CLINICAL MEDICINE 2000; 135:96-104. [PMID: 10638700 DOI: 10.1016/s0022-2143(00)70026-6] [Citation(s) in RCA: 68] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
We studied peripheral blood erythrocyte parameters and HFE genotypes in 94 hemochromatosis probands and 132 white, normal control subjects. Mean red blood cell counts in probands and control subjects were not significantly different. However, mean values of hemoglobin, hematocrit, mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), and mean corpuscular hemoglobin concentration (MCHC) were significantly higher in C282Y/C282Y probands (n = 60) than in wild-type control subjects (n = 65). Probands with other HFE genotypes also had increased mean erythrocyte parameters (other than red blood cell count). Peripheral blood smears prepared before therapeutic phlebotomy revealed that erythrocytes in many probands had increased diameters and were well filled with hemoglobin. Erythrocyte parameters were similar in C282Y/C282Y probands with and without hepatomegaly, elevated serum concentrations of hepatic enzymes, hepatic cirrhosis, diabetes mellitus, arthropathy, or hypogonadism. Among C282Y/C282Y probands, significantly greater values of MCV (but not other erythrocyte parameters) occurred among those who had transferrin saturation values of 75% or greater or iron overload at diagnosis. After iron depletion, the mean MCV, MCH, and MCHC values of C282Y/C282Y probands decreased but remained significantly greater than values in wild-type control subjects. Mean values of prephlebotomy MCH and MCHC concentrations were lower in HLA-A3-positive than in HLA-A3-negative C282Y/C282Y probands. We conclude that increased values of mean hemoglobin, hematocrit, MCV, MCH, and MCHC in hemochromatosis probands are caused primarily by increased iron uptake and hemoglobin synthesis by immature erythroid cells. Mechanisms of iron uptake by erythrocytes that could explain these results are discussed.
Collapse
|
37
|
Abstract
BACKGROUND There has been no estimate of the potential eligibility of hemochromatosis probands or patients as blood donors or the suitability for transfusion of their blood that was removed by therapeutic phlebotomy. STUDY DESIGN AND METHODS According to guidelines of the American Association of Blood Banks, a retrospective estimate of these factors in 211 adult white hemochromatosis probands diagnosed during routine medical care was performed. The findings were compared to those in volunteer white whole-blood donors. RESULTS Before diagnosis of hemochromatosis, 49 probands had voluntarily donated 597 units of blood; 88 percent were donated by men. After diagnosis, 142 (67%) of 211 probands were potentially eligible. Data on each unit removed during iron-depletion therapy and during the first year of maintenance therapy (therapeutic phlebotomy) were available in 86 eligible probands. Of 1592 units, 1029 (65%) obtained during iron-depletion therapy in eligible probands were potentially suitable; 86 percent were from men. During maintenance therapy, 106 (88%) of 121 units from eligible probands were potentially suitable. In volunteer donors, 255,567 (94%) of 273,302 presenting donors were accepted. After testing and laboratory losses, 239,300 (94%) units were acceptable for transfusion. CONCLUSIONS In comparison with normal volunteers, hemochromatosis probands at diagnosis are less likely to be eligible as blood donors. The percentage of units obtained from patients during iron-depletion therapy that are suitable for transfusion is also lower, although the percentage increases during maintenance therapy.
Collapse
|
38
|
Barton JC, Sawada-Hirai R, Rothenberg BE, Acton RT. Two novel missense mutations of the HFE gene (I105T and G93R) and identification of the S65C mutation in Alabama hemochromatosis probands. Blood Cells Mol Dis 1999; 25:147-55. [PMID: 10575540 DOI: 10.1006/bcmd.1999.0240] [Citation(s) in RCA: 128] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Sequencing of HFE exons 2, 3, 4, and 5, and of portions of introns 2, 4, and 5 revealed novel mutations in four of twenty hemochromatosis probands who lacked C282Y homozygosity, C282Y/H63D compound heterozygosity, or H63D homozygosity. Probands 1 and 2 were heterozygous for previously undescribed mutations: exon 2, nt 314T-->C (314C; I105T), and exon 2, nt 277G-->(277C; G93R), respectively; these probands were also heterozygous for H63D and C282Y, respectively. Probands 3 and 4 were heterozygous for a previously described but uncommon HFE mutation: exon 2, nt 193A-->T (193T; S65C). Proband 3 was also heterozygous for C282Y and had porphyria cutanea tarda, and Proband 4 had hereditary stomatocytosis. Each of these four probands had iron overload. In each proband with an uncommon HFE coding region mutation, I105T, G93R, and S65C occurred on separate chromosomes from those with the C282Y or H63D mutations. Neither I105T, G93R, nor S65C occurred as spontaneous mutations in our probands. The I105T and G93R mutations were linked to haplotypes bearing HLA-A3,-B7 and HLA-A2,-B62, respectively. The S65C mutation was linked to a haplotype characterized by HLA-32. Sixteen other probands did not have an uncommon HFE exon mutation. In 176 normal control subjects, two were heterozygous for S65C, but I105T and G93R were not detected. Nine of twenty probands were heterozygous and two probands were homozygous for a previously described base-pair change at intron 2, nt 3671T-->C. One proband without a detectable missense mutation had a previously described intron 5 allele (nt 6700G-->A). Heterozygosity for a previously described base-pair change in intron 4 (nt 5636T-->C) was detected in all persons we studied who also had the S65C mutation. One proband was heterozygous for a previously undescribed base-pair change at intron 5 (nt 5807A-->G). We conclude that uncommon HFE exon and intron mutations may be discovered among hemochromatosis patients who have "atypical" HFE genotypes.
Collapse
|
39
|
Abstract
BACKGROUND Dermatologic disease in HIV-infected women has not been adequately characterized. OBJECTIVE The main purposes of this study were to characterize nongenital dermatologic disease in HIV-infected women and correlate these diagnoses with CD4 lymphocyte count to compare these findings with those in published reports of men. METHODS This study was a retrospective chart review of female patients with dermatologic diagnoses followed up at an HIV clinic in New York City, seen by either a dermatologist (49 patients) and/or a primary care practitioner (114 patients). CD4 lymphocyte count was recorded if available within 6 months of diagnosis; mean CD4 count was calculated for all disorders with 5 or more diagnoses. RESULTS Oropharyngeal candidiasis, drug eruption, dermatophytosis, rash (not otherwise specified), nongenital herpes simplex, herpes zoster, and seborrheic dermatitis were the most prevalent diagnoses made by primary care providers. Itchy red bump disease, acne, atopic dermatitis, xerosis, seborrheic dermatitis, nongenital warts, and molluscum contagiosum were the most prevalent diagnoses made by the dermatologist. Mean CD4 lymphocyte count was lowest in itchy red bump disease, nongenital warts, nongenital herpes simplex, xerosis, and drug eruptions. CONCLUSION There appears to be no appreciable difference in the spectrum or prevalence of dermatologic disease in HIV-infected women versus HIV-infected men, except for a lower prevalence of Kaposi's sarcoma, oral hairy leukoplakia, and possibly onychomycosis in women. The degree of immunosuppression associated with various dermatoses in HIV-infected women is similar to that in men, except perhaps for molluscum contagiosum, which may appear earlier in women.
Collapse
|
40
|
McDonnell SM, Grindon AJ, Preston BL, Barton JC, Edwards CQ, Adams PC. A survey of phlebotomy among persons with hemochromatosis. Transfusion 1999; 39:651-6. [PMID: 10378847 DOI: 10.1046/j.1537-2995.1999.39060651.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
BACKGROUND One in 10 whites in the United States is a carrier for hemochromatosis and an estimated 1 in 200 is clinically affected. Early treatment with therapeutic phlebotomy to remove excess iron can prevent associated chronic diseases. However, little information is available on the amount of blood withdrawn or the rates of withdrawal from hemochromatosis patients. The patterns of therapeutic phlebotomy and the magnitude of charges in persons with hemochromatosis were surveyed. STUDY DESIGN AND METHODS Surveys were mailed to persons with hemochromatosis identified by health care providers, blood centers, patient advocacy groups, and the Internet. There were 2362 respondents to the survey from the United States. RESULTS Thirty-seven percent of respondents reported being voluntary blood donors prior to diagnosis. The mean rate of therapeutic phlebotomy for iron depletion was 2.6 units per month (mean duration, 13 months). The mean rate of maintenance phlebotomy was 0.5 units per month. Therapeutic phlebotomy rates varied by sex, age, reason for diagnosis, and severity of symptoms. Seventy-six percent of respondents reported full or partial insurance coverage of therapeutic phlebotomy charges. Seventy-six percent received therapeutic phlebotomy services in a hospital or physician's office and 30 percent in a blood center. Charges for therapeutic phlebotomy varied by site, with a mean cost of $90 in hospitals and $52 in blood centers. Fifty-four percent of respondents attempted to donate blood after their diagnosis but were excluded. CONCLUSION The amount of blood withdrawn from persons with hemochromatosis is substantial. The location where patients received phlebotomy services appears to be influenced by charges and time since diagnosis.
Collapse
|
41
|
McDonnell SM, Preston BL, Jewell SA, Barton JC, Edwards CQ, Adams PC, Yip R. A survey of 2,851 patients with hemochromatosis: symptoms and response to treatment. Am J Med 1999; 106:619-24. [PMID: 10378618 DOI: 10.1016/s0002-9343(99)00120-5] [Citation(s) in RCA: 158] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
PURPOSE Hemochromatosis is a genetic disorder of iron absorption that affects 5 per 1,000 persons and is associated with reduced health and quality of life. We sought to determine the type and frequency of symptoms that patients experienced before the diagnosis and the treatments that they received. METHODS We mailed a questionnaire to 3,562 patients with hemochromatosis who were located using patient advocacy groups, physicians, blood centers, newsletters, and the Internet. RESULTS Of the 2,851 respondents, 99% were white and 62% were men. Circumstances that led to diagnosis of hemochromatosis included symptoms (35%), an abnormal laboratory test (45%), and diagnosis of a family member with hemochromatosis (20%). The mean (+/- SD) age of symptom onset was 41 +/- 14 years. Symptoms had been present for an average of 10 +/- 10 years before the diagnosis was made. Among the 58% of patients with symptoms, 65% had physician-diagnosed arthritis and 52% had liver disease. The most common and troublesome symptoms were extreme fatigue (46%), arthralgia (44%), and loss of libido (26%). Physician instructions to patients included treatment with phlebotomy (90%), testing family members (75%), and avoiding iron supplements (65%). CONCLUSIONS The diagnosis of hemochromatosis in most patients was delayed. Physician education is needed to increase the detection of patients with the disease and to improve its management.
Collapse
|
42
|
Barton JC, Rothenberg BE, Bertoli LF, Acton RT. Diagnosis of hemochromatosis in family members of probands: a comparison of phenotyping and HFE genotyping. Genet Med 1999; 1:89-93. [PMID: 11336458 DOI: 10.1097/00125817-199903000-00005] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
PURPOSE We wanted to compare phenotyping and HFE genotyping for diagnosis of hemochromatosis in 150 family members of 61 probands. METHODS Phenotypes were defined by persistent transferrin saturation elevation, iron overload, or both; genotypes were defined by HFE mutation analysis. RESULTS Twenty-five family members were C282Y homozygotes; 23 of these (92%) had a hemochromatosis phenotype. Twenty-three family members had HFE genotype C282Y/H63D; eight of these (35%) had a hemochromatosis phenotype. Six of 102 (6%) family members who inherited other HFE genotypes had a hemochromatosis phenotype. CONCLUSION Phenotyping and genotyping are complementary in diagnosing hemochromatosis among family members of probands.
Collapse
|
43
|
Barton JC, Beutler E, Gelbart T. Coinheritance of alleles associated with hemochromatosis and hereditary hyperferritinemia-cataract syndrome. Blood 1998; 92:4480. [PMID: 9882097] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023] Open
|
44
|
Barton JC, McDonnell SM, Adams PC, Brissot P, Powell LW, Edwards CQ, Cook JD, Kowdley KV. Management of hemochromatosis. Hemochromatosis Management Working Group. Ann Intern Med 1998; 129:932-9. [PMID: 9867745 DOI: 10.7326/0003-4819-129-11_part_2-199812011-00003] [Citation(s) in RCA: 204] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The complications of iron overload in hemochromatosis can be avoided by early diagnosis and appropriate management. Therapeutic phlebotomy is used to remove excess iron and maintain low normal body iron stores, and it should be initiated in men with serum ferritin levels of 300 microg/L or more and in women with serum ferritin levels of 200 microg/L or more, regardless of the presence or absence of symptoms. Typically, therapeutic phlebotomy consists of 1) removal of 1 unit (450 to 500 mL) of blood weekly until the serum ferritin level is 10 to 20 microg/L and 2) maintenance of the serum ferritin level at 50 microg/L or less thereafter by periodic removal of blood. Hyperferritinemia attributable to iron overload is resolved by therapeutic phlebotomy. When applied before iron overload becomes severe, this treatment also prevents complications of iron overload, including hepatic cirrhosis, primary liver cancer, diabetes mellitus, hypogonadotrophic hypogonadism, joint disease, and cardiomyopathy. In patients with established iron overload disease, weakness, fatigue, increased hepatic enzyme concentrations, right upper quadrant pain, and hyperpigmentation are often substantially alleviated by therapeutic phlebotomy. Patients with liver disease, joint disease, diabetes mellitus and other endocrinopathic abnormalities, and cardiac abnormalities often require additional, specific management. Dietary management of hemochromatosis includes avoidance of medicinal iron, mineral supplements, excess vitamin C, and uncooked seafoods. This can reduce the rate of iron reaccumulation; reduce retention of nonferrous metals; and help reduce complications of liver disease, diabetes mellitus, and Vibrio infection. This comprehensive approach to the management of hemochromatosis can decrease the frequency and severity of iron overload, improve quality of life, and increase longevity.
Collapse
|
45
|
Burke W, Thomson E, Khoury MJ, McDonnell SM, Press N, Adams PC, Barton JC, Beutler E, Brittenham G, Buchanan A, Clayton EW, Cogswell ME, Meslin EM, Motulsky AG, Powell LW, Sigal E, Wilfond BS, Collins FS. Hereditary hemochromatosis: gene discovery and its implications for population-based screening. JAMA 1998; 280:172-8. [PMID: 9669792 DOI: 10.1001/jama.280.2.172] [Citation(s) in RCA: 191] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
OBJECTIVE To evaluate the role of genetic testing in screening for hereditary hemochromatosis to help guide clinicians, policymakers, and researchers. PARTICIPANTS An expert panel was convened on March 3, 1997, by the Centers for Disease Control and Prevention (CDC) and the National Human Genome Research Institute (NHGRI), with expertise in epidemiology, genetics, hepatology, iron overload disorders, molecular biology, public health, and the ethical, legal, and social implications surrounding the discovery and use of genetic information. EVIDENCE The group reviewed evidence regarding the clinical presentation, natural history, and genetics of hemochromatosis, including current data on the candidate gene for hemochromatosis (HFE) and on the ethical and health policy implications of genetic testing for this disorder. CONSENSUS PROCESS Consensus was achieved by group discussion confirmed by a voice vote. A draft of the consensus statement was prepared by a writing committee and subsequently reviewed and revised by all members of the expert group over a 1-year period. CONCLUSIONS Genetic testing is not recommended at this time in population-based screening for hereditary hemochromatosis, due to uncertainties about prevalence and penetrance of HFE mutations and the optimal care of asymptomatic people carrying HFE mutations. In addition, use of a genetic screening test raises concerns regarding possible stigmatization and discrimination. Tests for HFE mutations may play a role in confirming the diagnosis of hereditary hemochromatosis in persons with elevated serum iron measures, but even this use is limited by uncertainty about genotype-phenotype correlations. To address these questions, the expert group accorded high priority to population-based research to define the prevalence of HFE mutations, age and sex-related penetrance of different HFE genotypes, interactions between HFE genotypes and environmental modifiers, and psychosocial outcomes of genetic screening for hemochromatosis.
Collapse
|
46
|
Abstract
PURPOSE To evaluate factors that lead to the diagnosis of hemochromatosis probands in a community hospital, including education of physicians about hemochromatosis and iron overload, specialty of physicians, diagnostic indicators of hemochromatosis, and clinical manifestations of hemochromatosis probands. PATIENTS AND METHODS We conducted a hemochromatosis education program for health care personnel associated with a community hospital and the public during 1990 to 1994. Data on physicians who diagnosed probands, diagnostic indicators of hemochromatosis, and manifestations of hemochromatosis and associated illnesses were tabulated. Iron grades of all hospital liver biopsy specimens obtained from Caucasian subjects during 1990 to 1994 were also analyzed. RESULTS We identified 162 hemochromatosis probands; 66.7% were diagnosed by physicians who participated in our education program. Primary care and internal medicine subspecialty physicians diagnosed 66.7% and 29.6% of probands, respectively, based on elevated serum iron parameters and hepatic enzyme concentrations (51.9% and 36.4% of probands, respectively). Iron overload occurred in 90.7%, and was associated with clinical manifestations in most. Of 844 hospital liver biopsy specimens from Caucasians, 8.5% had increased iron grades; 4.6% represented hemochromatosis. CONCLUSIONS Physicians with current education readily diagnose hemochromatosis probands during routine health care delivery, but most probands identified in this manner have iron overload. Our results suggest that community physicians and hospitals could contribute substantially to hemochromatosis screening programs, permitting detection of more homozygotes before the development of iron overload.
Collapse
|
47
|
|
48
|
Barton JC, Shih WW, Sawada-Hirai R, Acton RT, Harmon L, Rivers C, Rothenberg BE. Genetic and clinical description of hemochromatosis probands and heterozygotes: evidence that multiple genes linked to the major histocompatibility complex are responsible for hemochromatosis. Blood Cells Mol Dis 1997; 23:135-45; discussion 145a-b. [PMID: 9215758 DOI: 10.1006/bcmd.1997.0129] [Citation(s) in RCA: 115] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
We evaluated Alabama hemochromatosis probands (n = 74) and normal control subjects (n = 142) for expression of the hemochromatosis-associated mutations nt 845G-->A (845A; Cys282Tyr) and nt 187C-->G (His63Asp) in a gene linked to the major histocompatibility complex (MHC). We also tabulated parameters of iron metabolism and iron overload in probands and in obligate heterozygote family members of homozygous Cys282Tyr probands. Among probands, 59.4% were Cys282Tyr homozygotes and 20.3% were heterozygotes; 20.3% did not express this mutation. In normal control subjects, 14.7% were heterozygous for the Cys282Tyr mutation; one normal control subject was homozygous for the Cys282Tyr mutation. None (0 of 44) of our Cys282Tyr-homozygous hemochromatosis probands had the His63Asp mutation. Of the Cys282Tyr-heterozygous and -negative probands, the His63Asp mutation occurred in 26.7% (4/15) and 53.3% (8/15), respectively. In normal control subjects, 23.2% were heterozygous for the His63Asp mutation; 2.8% were homozygous. Induction phlebotomy requirements and other manifestations of iron overload were significantly greater in Cys282Tyr homozygotes than among other probands. Cys282Tyr-heterozygous probands had significantly higher values of serum iron parameters than did obligate Cys282Tyr heterozygotes whose values were, on the average, normal. Co-expression of HLA-A3, HLA-B7, and D6S105(8) was significantly more frequent in all subgroups of probands stratified by Cys282Tyr expression than in normal control subjects. These results demonstrate that the severity of iron overload in hemochromatosis is affected significantly by genetic factors. Further, our findings support the hypothesis that one or more MHC-linked genes other than that corresponding to the Cys282Tyr and His63Asp mutations contributes to increased iron absorption and iron overload in hemochromatosis probands.
Collapse
|
49
|
|
50
|
Barton JC, Harmon L, Rivers C, Acton RT. Hemochromatosis: association of severity of iron overload with genetic markers. Blood Cells Mol Dis 1996; 22:195-204. [PMID: 9075570 DOI: 10.1006/bcmd.1996.0100] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
We postulated that the severity of iron overload in homozygous hemochromatosis probands is related to the expression of HLA-A3 or D6S105 allele 8. Therefore, we used these markers to characterize Alabama hemochromatosis probands and normal control subjects. We then quantified the blood removed by phlebotomy to exhaust body iron stores and maintain normal serum ferritin concentrations in our hemochromatosis probands. Induction and maintenance phlebotomy requirements were significantly greater in presumed HLA-A3 homozygotes or in D6S105 allele 8 homozygotes than in homozygous probands lacking these markers. Intermediate values were observed in probands who were HLA-A3 or allele 8 heterozygotes, respectively. We also analyzed data from males and females separately. Among subjects of the same sex, the induction and maintenance phlebotomy requirements in subjects presumed to be HLA-A3 homozygotes or in allele 8 homozygotes were greater than those of other groups. Our results support the hypothesis that the severity of iron overload in hemochromatosis is determined predominantly by genetic factors, and provide evidence that two or more mutations for hemochromatosis exist. However, the design of our study does not permit a distinction to be made between allelic and locus heterogeneity for the hemochromatosis gene(s).
Collapse
|